With a set of computerized instructions and flashes of infrared light, up to 1,024 tiny robots organized themselves into the shape of a starfish, the letter K and other complex designs, researchers report August 15 in Science. The robots' collective behavior mimics the way 100,000 ants quickly build bridges or rafts or thousands of birds move together in a flock. Successfully programming the thousand-bot swarm to coordinate its behavior is a step forward in collective artificial intelligence.